Biomedical subjects

A C Fisher

Publications and source records attributed to A C Fisher.

At least 19 recordsLinked to original sources

PubMed2001

Hydrodynamic potential-modulated reflectance spectroscopy: theory and experiment.

This article describes the development and application of a new electrochemical methodology based on potential-modulated UV-vis reflectance spectroscopy (PMRS). The device configuration is based upon a thin-layer flow-through channel cell incorporating a platinum working electrode. Reagent solutions are pumped through the cell under well-defined hydrodynamic conditions and electrolyzed at the platinum working electrode. Measurements are presented for linear sweep and fixed dc potentials with a superimposed small amplitude sinusoidal potential perturbation. A UV-vis source is employed to irradiate the electrode region, and the resulting reflected signal is analyzed using a phase sensitive detector. Experimental studies using tris(4-bromophenyl) amine (TBPA) in acetonitrile are presented which quantify the relationship between the absorption spectrum and reflected light intensity as a function of the transport rate, electrolysis reactions, and the modulation frequency of the incident irradiation. The experimental results are analyzed using numerical simulations based on a finite difference strategy. These permit the quantitative prediction of the concentration distribution of reagents within the cell. A fast Fourier transform (FFT) routine was used to analyze the frequency response of the numerically predicted reflectance signal. Excellent agreement was observed between the numerical predictions and experimental observations.

Journal Article↗

PubMed2001

Evaluation of contraceptive efficacy and cycle control of a transdermal contraceptive patch vs an oral contraceptive: a randomized controlled trial.

CONTEXT: Oral contraceptive (OC) pills are effective, but poor compliance increases rates of pregnancy during treatment. OBJECTIVE: To compare the contraceptive efficacy, cycle control, compliance, and safety of a transdermal contraceptive patch and an OC. DESIGN: Randomized, open-label, parallel-group trial conducted October 1997 to June 1999. SETTING: Forty-five clinics in the United States and Canada. PARTICIPANTS: A total of 1417 healthy adult women of child-bearing potential. INTERVENTIONS: Participants were randomly assigned to receive a transdermal contraceptive patch (n = 812) vs an OC (n = 605) for 6 or 13 cycles. Patch treatment consisted of application of 3 consecutive 7-day patches followed by 1 patch-free week. MAIN OUTCOME MEASURES: Overall and method-failure Pearl Indexes (number of pregnancies/100 person-years of use) and life-table estimates of the probability of pregnancy were calculated. Cycle control, compliance, patch adhesion, and adverse events were also assessed. RESULTS: Overall and method-failure Pearl Indexes were numerically lower with the patch (1.24 and 0.99, respectively) vs the OC (2.18 and 1.25, respectively); this difference was not statistically significant (P =.57 and.80, respectively). The incidence of breakthrough bleeding and/or spotting was significantly higher only in the first 2 cycles in the patch group, but the incidence of breakthrough bleeding alone was comparable between treatments in all cycles. The mean proportion of participants' cycles with perfect compliance was 88.2% (811 total participants, 5141 total cycles) with the patch and 77.7% (605 total participants, 4134 total cycles) with the OC (P <.001). Only 1.8% (300/16 673) of patches completely detached. Both treatments were similarly well tolerated; however, application site reactions, breast discomfort, and dysmenorrhea were significantly more common in the patch group. CONCLUSION: The contraceptive patch is comparable to a combination OC in contraceptive efficacy and cycle control. Compliance was better with the weekly contraceptive patch than with the OC.

Administration, Cutaneous↗

PubMed2001

Comparison of a novel norgestimate/ethinyl estradiol oral contraceptive (Ortho Tri-Cyclen Lo) with the oral contraceptive Loestrin Fe 1/20.

This multicenter study compared the contraceptive efficacy, cycle control, and safety of a new triphasic norgestimate (180/215/250 microg)/ethinyl estradiol 25 microg regimen (Ortho Tri-Cyclen Lo) (n = 1,723) with that of norethindrone acetate 1 mg/ethinyl estradiol 20 microg (Loestrin Fe 1/20) (n = 1,171). Healthy women were treated for up to 13 cycles. Demographics were similar between regimens. Contraceptive efficacy was comparable for Ortho Tri-Cyclen Lo and Loestrin Fe 1/20. The overall and method failure probabilities of pregnancy through 13 cycles were 1.9% and 1.5%, respectively, with Ortho Tri-Cyclen Lo and 2.6% and 2.4%, respectively, with Loestrin Fe 1/20. Breakthrough bleeding and spotting was reported by a significantly lower percentage of participants in the Ortho Tri-Cyclen Lo group compared with the Loestrin Fe 1/20 group. At representative Cycles 1, 3, 6, 9, and 13, breakthrough bleeding and spotting rates were 16.3, 11.5, 10.3, 7.9, and 7.7%, respectively, in the Ortho Tri-Cyclen Lo group and 34.9, 22.9, 22.2, 15.9, and 13.1%, respectively, in the Loestrin Fe 1/20 group. Compliance and safety data were similar for the two regimens.

Administration, Oral↗

PubMed2001

Efficacy and safety of a transdermal contraceptive system.

OBJECTIVES: To evaluate the efficacy, cycle control, compliance, and safety of a transdermal contraceptive system that delivers norelgestromin 150 microg and ethinyl estradiol 20 microg daily. METHODS: In this open-label, 73-center study, 1672 healthy, ovulatory, sexually active women received ORTHO EVRA/EVRA for six (n = 1171) or 13 cycles (n = 501). The treatment regimen for each cycle was three consecutive 7-day patches (21 days) followed by 1 patch-free week. RESULTS: The overall and method-failure probabilities of pregnancy through 13 cycles were 0.7% and 0.4%, respectively. The incidence of breakthrough bleeding was low throughout the study. Perfect compliance (21 consecutive days of dosing, followed by a 7-day drug-free interval; no patch could be worn for more than 7 days) was achieved in 90% of subject cycles; only 1.9% of patches detached completely. Adverse events were typical of hormonal contraception, and most were mild-to-moderate in severity and not treatment limiting. The most common adverse events resulting in discontinuation were application site reactions (1.9%), nausea (1.8%), emotional lability (1.5%), headache (1.1%), and breast discomfort (1.0%). CONCLUSIONS: The transdermal contraceptive patch provides effective contraception and cycle control, and is well tolerated. The weekly change schedule for the contraceptive patch is associated with excellent compliance and wearability characteristics.

Administration, Cutaneous↗

PubMed2001

Transdermal contraception.

This review summarizes the clinical studies involving the once-weekly Ortho Evra/Evra contraceptive patch. The patch delivers norelgestromin (NGMN), 150 microg, and ethinyl estradiol (EE), 20 microg, daily to the systemic circulation. The contraceptive patch provided ovulation suppression and cycle control similar to that of oral norgestimate 250 microg/EE 35 microg, significantly decreased mean maximum follicular diameter following a 3-day intentional delayed dosing phase when compared with oral levonorgestrel (LNG) 50/75/125 microg/EE 30/40/30 micorg and oral LNG 100 microg/EE 20 microg, and was as effective as oral LNG 50/75/125 microg/EE 30/40/30 microg and oral desogestrel 150 microg/EE 20 microg in altering cervical mucus composition (i.e., creating a scanty, viscous consistency). The contraceptive patch provided efficacy, cycle control, and safety comparable to that seen with oral LNG 50/75/125 microg/EE 30/40/30 microg, but women were able to correctly follow the weekly dosing regimen significantly more often than the daily oral contraceptive dosing regimen. Less than 2% of patches were replaced because of complete detachment in these trials. The patch was not associated with phototoxicity or photoallergy. The contraceptive patch, the only noninvasive, weekly birth control method that a woman can self-administer, will be a valuable addition to current contraceptive options.

Administration, Cutaneous↗

PubMed1999

Monocular and binocular depth discrimination thresholds.

BACKGROUND: Measurement of stereoacuity at varying distances, by real or simulated depth stereoacuity tests, is helpful in the evaluation of patients with binocular imbalance or strabismus. Although the cue of binocular disparity underpins stereoacuity tests, there may be variable amounts of other binocular and monocular cues inherent in a stereoacuity test. In such circumstances, a combined monocular and binocular threshold of depth discrimination may be measured--stereoacuity conventionally referring to the situation where binocular disparity giving rise to retinal disparity is the only cue present. A child-friendly variable distance stereoacuity test (VDS) was developed, with a method for determining the binocular depth threshold from the combined monocular and binocular threshold of depth of discrimination (CT). METHODS: Subjects with normal binocular function, reduced binocular function, and apparently absent binocularity were included. To measure the threshold of depth discrimination, subjects were required by means of a hand control to align two electronically controlled spheres at viewing distances of 1, 3, and 6m. Stereoacuity was also measured using the TNO, Frisby, and Titmus stereoacuity tests. BTs were calculated according to the function BT= arctan (1/tan alphaC - 1/tan alphaM)(-1), where alphaC and alphaM are the angles subtended at the nodal points by objects situated at the monocular threshold (alphaM) and the combined monocular-binocular threshold (alphaC) of discrimination. RESULTS: In subjects with good binocularity, BTs were similar to their combined thresholds, whereas subjects with reduced and apparently absent binocularity had binocular thresholds 4 and 10 times higher than their combined thresholds (CT). The VDS binocular thresholds showed significantly higher correlation and agreement with the TNO test and the binocular thresholds of the Frisby and Titmus tests, than the corresponding combined thresholds (p = 0.0019). CONCLUSION: The VDS was found to be an easy to use real depth (distance) stereoacuity test. The method described for calculating the BT provides one simple nonlinear solution for determining the respective contributions of binocular and monocular (MT) depth discrimination to the combined depth threshold.

Adolescent↗

PubMed1999

A new capillary viscometer for whole blood viscosimetry.

A new capillary system was developed, incorporating infrared sensors, which allowed the determination of whole blood viscosity over a wide range of shear stresses. Flow conditions were defined by the geometry of the capillary and the sample pressure head. Whole blood was considered to be a power law fluid and a modified Mooney's formula was used for the calculation of the related invariants. The new viscometer proved to be very simple in use, requiring one run, had a short measuring time and utilised a small test sample volume. However it can be used for whole blood viscosity measurements only at medium and high shear stresses.

Blood Viscosity↗

PubMed1998

Macrophage--polymer interactions.

One of the most notable and initial indications of the body's response to an implanted material is the inflammatory response, a process which is known to be largely influenced by the activation of macrophages and other cell types. Thus, the magnitude of the inflammatory response can be related to the level of activation of macrophages. As certain well defined morphological changes are known to accompany cell activation, we quantitatively evaluated the cell--substrate interactions, between a range of polymeric materials and isolated macrophages in vitro, using microscopy and image analysis. This enabled us to assess the morphology of the cells, and how the morphology of the macrophages was influenced by changes in time and substrate. This method provided detailed images which were used to evaluate cell-substrate interactions. It was found that, polyurethane (PU) and poly(dimethylsiloxane) (Si) samples displayed a similar pattern in cell behaviour, whilst macrophages placed in contact with polyvinylchloride (PVC) samples continually displayed a more activated morphology with increasing time throughout the test period. As well as providing a detailed analysis of cell-substrate interactions this study also highlighted the advantages of employing an image analysis program for a more comprehensive and reproducible form of assessment of cellular morphology.

Biocompatible Materials↗

PubMed1997

The public release of hospital and physician mortality data in Pennsylvania. A case study.

OBJECTIVES: Using the public reports of the Pennsylvania Health Care Cost Containment Council on coronary artery bypass graft surgery for 1990 to 1992 as a case study, the authors assess the sensitivity of results to the choice of data and statistical methodology. METHODS: Using the Council's public-release data, surgical mortality and utilization were reanalyzed by standard linear models, empirical Bayes methods, Monte Carlo simulations, and hierarchical statistical models. RESULTS: Statistical power calculations demonstrate that the annual volume of bypass surgery for many hospitals and for most surgeons is too small for meaningful mortality comparisons. The number of hospitals and physicians designated as mortality "outliers" in the Council's reports results in part from a failure to adjust critical P values for multiple comparisons. Hierarchical statistical models implemented by mixed effects logistic regression, by contrast, can detect true differences in performance without producing false outliers. Mortality analyses are sensitive to the choice of comorbidities used for severity adjustment of a mortality model. Small-area analyses indicate large differences in the rates of bypass surgery across Pennsylvania, with lower population-based rates of surgery associated with higher population-based inpatient mortality. CONCLUSIONS: Analyses of mortality by operative procedure, rather than by patient diagnosis, should consider the potential for selection bias caused by the decision to elect surgery. The clinical and statistical issues of operative mortality are sufficiently complex to merit review by independent experts before public release of hospital and physician performance measures.

Cardiology Service, Hospital↗

PubMed1997

Endothelial-borne platelet-activating factor and interleukin-8 rapidly immobilize rolling neutrophils.

The kinetics of the response of integrins to activating signal(s) must be rapid to ensure that rolling neutrophils are localized at the sites of inflammation. From video records, we analyzed the adhesion of individual neutrophils in a flow-based in vitro model of endothelial hypoxia and reoxygenation. There were numerous rolling interactions between flowing neutrophils and P-selectin on human umbilical vein endothelial cells after hypoxia, but 90% lasted for < 1 s, with approximately 30% converted to stationary attachment via beta 2-integrin(s). Interleukin-8 (IL-8) and platelet-activating factor (PAF) were responsible for neutrophil activation in this model [G. E Rainger, A. Fisher, C. Shearman, and G. B. Nash. Am. J. Physiol. 269 (Heart Circ. Physiol. 38): H1398-H1406, 1995]. In the presence of a PAF-receptor antagonist, IL-8 acting alone induced conversion of rolling to stationary adhesion in as little as 80 ms after the initial attachment of a neutrophil, with a median response time of 240 ms. In the presence of a monoclonal antibody that neutralized IL-8 activity, PAF acting alone required a minimum duration of rolling of 560 ms to promote stationary adhesion, with a significantly longer median duration of 720 ms. In a reconstituted model, treatment of endothelial cells with hydrogen peroxide induced short-lived rolling of neutrophils supported by P-selectin. Exogenously added IL-8 and/or PAF bound to the endothelial surface and successfully induced the immobilization of neutrophils. Rapid and distinct kinetics of the conversion to stationary adhesion were observed again for IL-8 or PAF. Thus although endothelial-presented signals differed in their rate of action, neutrophils could be localized within one or two endothelial cell diameters of their initial adhesive contact point.

Cell Adhesion↗

PubMed1996

New polyurethane heart valve prosthesis: design, manufacture and evaluation.

In light of the thrombogenicity of mechanical valves and the limited durability of bioprosthetic valves, alternative designs and materials are being considered for prosthetic heart valves. A new tri-leaflet valve, made entirely from polyurethane, has been developed. The valve comprises three thin polyurethane leaflets (approximately 100 microns thick) suspended from the inside of a flexible polyurethane frame. The closed leaflet geometry is elliptical in the radial direction and hyperbolic in the circumferential direction. Valve leaflets are formed and integrated with their support frame in a single dip coating operation. The dipping process consistently gives rise to tolerably uniform leaflet thickness distributions. In hydrodynamic tests, the polyurethane valve exhibits pressure gradients similar to those for a bioprosthetic valve (St Jude Bioimplant), and levels of regurgitation and leakage are considerably less than those for either a bi-leaflet mechanical valve (St Jude Medical) or the bioprosthetic valve. Six out of six consecutively manufactured polyurethane valves have exceeded the equivalent of 10 years function without failure in accelerated fatigue tests. The only failure to date occurred after the equivalent of approximately 12 years cycling, and three valves have reached 527 million cycles (approximately 13 years equivalent). The simplicity of valve manufacture, combined with promising results from in vitro testing, indicate that further evaluation is warranted.

Biocompatible Materials↗

PubMed1996

The prognostic significance of serum viral load, codon 215 reverse transcriptase mutation and CD4+ T cells on progression of HIV disease in a double-blind study of thymopentin.

OBJECTIVE: To determine in asymptomatic HIV-infected subjects the prognostic value of virion reverse transcriptase (RT) codon 215 mutation, serum HIV RNA level, CD4+ T-cell count and immune complex dissociated (ICD) p24 level. The retrospective evaluation of thymopentin treatment effect on subjects in high risk groups for progression was a secondary objective. PARTICIPANTS: Zidovudine (ZDV)-experienced asymptomatic HIV-infected subjects (n = 352) who had been enrolled in a 48-week placebo-controlled double-blind trial of thymopentin treatment were studied. METHODS: Post hoc analyses were conducted to determine which subjects at study entry were at greater risk for progression to AIDS-related complex (ARC), AIDS or death, and to determine the effect of treatment on these subjects. Four potential prognostic variables (virion RT codon 215 mutation, circulating HIV virion RNA copies, CD4+ T-cell count, and ICD p24) were evaluated by dichotomizing subjects for each variable based on the median of the observed values. CD4+ T-cell count was evaluated prospectively, whereas frozen samples were evaluated under blinded conditions for the other variables after the study was completed. RESULTS: The presence of the codon 215 mutation [P = 0.044; relative hazard (RH), 2.6], > or = 20,000 HIV RNA copies/ml (P = 0.002; RH, 5.5), and < 350 CD4+ cells 10(6)/l (P = 0.042; RH, 2.2) were prognostic factors, and > or = 30 pg/ml ICD p24 level (P = 0.52; RH, 1.4) was not a prognostic factor in predicting progression. Subjects were prestratified by previous ZDV use (< or = 6 or > 6 months). Across both strata thymopentin delayed treatment progression to ARC, AIDS, or death (P = 0.015; RH, 3.0). This effect was magnified in the ZDV-experienced subjects at greater risk, where thymopentin delayed progression compared to placebo in the presence of the codon 215 mutation (P = 0.007; RH, 10.1), > or = 20,000 RNA copies/ml (P = 0.012; RH, 8.9), and CD4+ T-cell count < 350 x 10(6)/l (P = 0.005; RH, 10.4). CONCLUSIONS: Codon 215 mutation, serum HIV RNA and CD4 T-cell count are independent predictors of progression in ZDV-experienced asymptomatic subjects. Furthermore, thymopentin delays HIV disease progression in the presence of a key ZDV resistance mutation as well as high viral load and low CD4+ T-cell counts.

Adjuvants, Immunologic↗

PubMed1996

Middle latency auditory evoked potentials during repeated transitions from consciousness to unconsciousness.

We have investigated the relationship between changes in the middle latency auditory evoked potentials during alternating periods of consciousness and unconsciousness produced by propofol infusion combined with spinal anaesthesia for total knee replacement. Eleven patients completed the study, of whom two had recollection of events after the onset of the anaesthetic. There were no significant differences in heart rate or systolic arterial pressure between any conscious and unconscious period. With the first change from consciousness to unconsciousness, latencies of Na, Pa and Nb increased from mean (SD) starting values of 20.0 (1.4), 31.7 (1.0) and 42.8 (1.6) ms to 22.5 (2.0), 39.3 (2.1) and 57.8 (4.4) ms, respectively. During successive transitions from unconsciousness to consciousness, awake latencies were slightly higher than those of baseline awake, whereas anaesthetised latencies were similar to the ones obtained during the first period of unconsciousness. The consistent changes demonstrated, suggest that the auditory evoked potentials could represent a reliable indicator of potential awareness during anaesthesia.

Aged↗

PubMed1996

In vitro function and durability assessment of a novel polyurethane heart valve prosthesis.

While flexible-leaflet, central-flow prosthetic heart valves promise relief from anticoagulation therapy, they continue to be restricted by inadequate durability. In consequence, a novel trileaflet valve, made entirely from polyurethane, has been developed. A batch of 6 consecutively manufactured polyurethane valves was subjected to hydrodynamic function and accelerated fatigue testing. Computerized data acquisition and control systems have been introduced to improve valve testing methodologies. In terms of hydrodynamic function, the polyurethane valve demonstrates transvalvular pressure gradients similar to those for a bioprosthetic valve (Carpentier-Edwards) and levels of retrograde flow significantly less than those for either the bioprosthetic valve or a bileaflet mechanical valve (St Jude Medical). The equivalent of 10 years of cycling without failure has been exceeded by all 6 polyurethane valves in accelerated fatigue tests with 2 valves remaining intact after 674 million cycles (equivalent to approximately 17 years) in continuing tests. Highspeed photography revealed considerable differences in leaflet motion between valves cycled at accelerated and physiological rates.

Biocompatible Materials↗

PubMed1995

In vitro assessment of water vapour transmission of synthetic wound dressings.

The water vapour transmission rate (WVTR) of 14 commercially available wound dressings (11 hydrocolloids, 2 hydrogels and 1 polyurethane film) was evaluated over 24 and 48 h periods using a modified ASTM standard method (ASTM E96-90). For the 48 h studies a novel microcomputer-controlled apparatus was employed. The dressings exhibited a wide range of WVTRs (76-9360 g m-2 d-1 at 24 h under forced air convection of 0.4 m s-1). The influence of air velocity of 0.4 m s-1 was not significant if the WVTR of the dressing was less than 880 g m-2 d-1 when measured under static air conditions. The influence of outer barrier layers and additional bandages on WVTR was also examined.

Bandages↗

PubMed1995

Effect of captopril, enalaprilat and mercaptopropionyl glycine (MPG) on the oxidative activity of human isolated neutrophils.

1. Neutrophil NADPH oxidase produces the superoxide anion (O2-) anion radical from oxygen. The thiol containing ACE inhibitor, captopril has been reported to inhibit isolated NADPH oxidase. The above effect of captopril, if present in intact cells, could contribute to the ability of this drug to alleviate neutrophil-mediated tissue damage. We have, therefore, investigated the effect of captopril on the oxidative activity of intact human isolated neutrophils. 2. The effects of captopril on neutrophil oxidative activity were compared with those of enalaprilat (a non-thiol ACE inhibitor) and N-mercaptopropionyl glycine (MPG) (a simple thiol). 3. The oxidative response of PMA-stimulated neutrophils measured by lucigenin chemiluminescence was not affected by any of these test agents. The thiol captopril and MPG (but not enalaprilat) caused an initial delay in luminol chemiluminescence production by PMA-stimulated neutrophils. 4. Captopril and MPG (but not enalaprilat) increased, rather than decreased oxygen uptake, when added to PMA-stimulated neutrophils. Thiol oxidation was determined to be, at least partly, responsible for the excess oxygen uptake observed. 5. NADPH oxidase activity in intact neutrophils was not affected by captopril, MPG or enalaprilat. The inhibition of NADPH oxidase activity is unlikely to contribute to the therapeutic effects of captopril and other thiols.

Acridines↗

PubMed1995

Does luminol chemiluminescence detect free radical scavengers?

Thiol compounds have been reported to abolish hypoxanthine/xanthine oxidase induced luminol chemiluminescence and this effect has been attributed to scavenging of superoxide (O2-)/(H2O2) produced from hypoxanthine/xanthine oxidase. Yet other workers have reported that thiol compounds have shown little, if any, reactivity towards O2-/H2O2. The aim of this study was to examine the discrepancy between these two sets of findings further. Captopril (a thiol angiotensin-converting enzyme (ACE) inhibitor) and MPG (a simple thiol) were observed to abolish hypoxanthine/xanthine oxidase induced chemiluminescence. The reactivity of captopril and MPG towards O2-/H2O2 was then determined by measurement of thiol oxidation in captopril and MPG after their incubation with hypoxanthine/xanthine oxidase. Incubation (at 10 min, 37 degrees C) with 4 mM hypoxanthine/0.03 u ml-1 xanthine oxidase resulted in 7% and 20% thiol oxidation in captopril and MPG (at 1 mM) respectively. Captopril and MPG, therefore, appeared to be ineffective scavengers of oxidants produced by hypoxanthine/xanthine oxidase. Captopril and MPG also did not affect urate production or oxygen consumption by xanthine oxidase which indicated that captopril and MPG quench luminol chemiluminescence by a mechanism that excludes the inhibition of xanthine oxidase. Hypoxanthine/xanthine oxidase induced luminol chemiluminescence may, therefore, be an unsuitable method for measuring free radical scavenging activity by drugs.

Antioxidants↗

PubMed1994

The effect of angiotensin-converting enzyme inhibitors on human neutrophil chemotaxis in vitro.

1. Myocardial 'reperfusion injury' has been partly attributed to the production of free radicals which are cytotoxic towards cells. Neutrophils are recruited by ischaemic tissue and are one source of free radicals. Angiotensin-converting enzyme (ACE) inhibitors can reduce 'reperfusion injury' and we decided to determine if ACE inhibitors might contribute to this effect by inhibiting neutrophil chemotaxis. 2. The effects of captopril (a thiol containing ACE inhibitor) and enalaprilat (a nonthiol ACE inhibitor) and N-mercaptopropionyl glycine (MPG) (a simple thiol) on neutrophil chemotaxis were tested in an in vitro Boyden chamber assay. 3. The chemotactic response of human neutrophils to fMLP was reduced by 27.6% with MPG (n = 8; P < 0.05), by 13.2% with enalaprilat (n = 8; P = 0.075) and by 5.2% with captopril (n = 8; P = 0.66) at 5 microM (therapeutic concentration.) 4. Neutrophil chemotaxis was significantly decreased with 50 microM and 500 microM MPG and enalaprilat and 500 microM captopril. 5. Supratherapeutic concentrations of ACE inhibitors can reduce neutrophil chemotaxis at high concentrations and this effect does not appear to be -SH dependent.

Captopril↗